1. Field of the Invention
The present invention relates generally to the field of pressure generators, and more particularly to an improved pressure generator which may superimpose a dynamic pressure on a static pressure.
2. Description of the Prior Art
Examples of earlier forms of pressure generators are shown in one or more of the following U.S. Pat. Nos. 3,590,626, 3,782,168, 3,868,844, 4,051,712 and 4,272,162.
Of these, U.S. Pat. No. 3,590,626 discloses a "Sinusoidal Pressure Calibrator" for use in calibrating piezoelectric pressure transducers. However, the entire apparatus, including the transducers-to-be-tested, was placed on a shaker table. Hence, since the transducers were shaken, there was an opportunity for introduction of spurious signals.